There are scenarios when a base station works under a high ambient temperature, some components may shut off due to a high temperature exceeding the limitation. For example, as part of a base station, RRU (Remote Radio Unit) includes one or more FPGAs (Field Programmable Gate Array). The RRU's power consumption is about 500 w or even higher. When the base station works in an ambient temperature of 45° C. with natural cooling, the temperature of FPGAs is close to its limitation 100° C. So the base station can not work under 55° C. due to failure of FPGAs. Thus, there is a need to cool down the FPGAs to ensure that the whole base station works under a high ambient temperature.